A143875 Number of ways of placing kings with no more than 2 mutual attacks on an n X n chessboard.

1, 2, 11, 155, 3280, 124511, 7623993, 795923016, 140176308483, 42642616703815

Offset

0,2

Links

Table of n, a(n) for n=0..9.

Crossrefs

Cf. A143870, A143881, A143886.

Cf. A143876, A143877, A143878, A143879, A143880.

Sequence in context: A227328 A287149 A188684 * A245054 A058154 A275923

Adjacent sequences: A143872 A143873 A143874 * A143876 A143877 A143878

Keyword

nonn,more,hard

Author

R. H. Hardin, Sep 04 2008

Status

approved